Various powered and/or manual instruments may use one or more removable tool bits, which may have different shapes and/or designs to accomplish different tasks. The instruments typically will include a bit holder to removably hold and/or secure one or more of the bits. Some bit holders may require manipulation by the user to secure and/or unsecure the desired bit to the bit holder. For example, a conventional three-jaw chuck requires the user to loosen the jaws to insert or remove the bit and to tighten the jaws to secure the bit. Other bit holders may automatically secure and/or lock the bit when the user inserts the bit into the bit holder. Alternatively, bit holders may require an external device, such as a key or tool, to secure and/or unsecure the bit to the bit holder.
Examples of bit holders may be found in U.S. Pat. Nos. 3,521,895; 3,767,218; 4,199,160; 4,209,182; 4,234,277; 4,626,152; 4,688,975; 4,692,073; 4,858,939; 4,946,179; 5,013,194; 5,062,749; 5,188,378; 5,398,946; 5,464,229; 5,709,391; 5,957,634; 6,062,779; 6,199,872; 6,270,085; 6,325,393; 6,311,989; 6,561,523; 6,612,586; 6,695,321; and 6,719,619; U.S. Patent Application Publication No. 2005/0116429; and Japanese Patent Application Publication No. JP2004050352. The complete disclosures of the above patents and patent application publications are herein incorporated by reference for all purposes.